Brush head manufacturing methods with protective coatings

ABSTRACT

A method for manufacturing a brush head includes the steps of providing a plurality of bristle tuft retention elements, and inserting at least one bristle tuft into each of the bristle tuft retention elements. The proximal end of each bristle tuft is secured into each bristle tuft retention element. The platen portion of the brush neck is positioned in relation to the proximal ends of the bristle tufts in the retaining elements to define a space in relation to the proximal ends of the bristle tufts. A flexible material is injected into the space to create a flexible material matrix that at least partially encompasses the neck and the proximal ends of the bristle tufts. At least a portion of an exterior of the flexible material matrix is coated with a protective coating.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application No.62/626,863 filed on Feb. 6, 2018, which application is incorporatedherein by reference in its entirety.

FIELD OF THE INVENTION

The present disclosure is directed generally to methods formanufacturing a brush head assembly with a protective coating or barrierapplied around the exterior of a flexible material matrix that retainsbristle tufts.

BACKGROUND

The brush heads of both manual and power toothbrushes comprise bristleswhich are used to clean the teeth, tongue, and cheeks. In sometoothbrushes, the bristles are stapled, or anchored into the neckportion of the brush head. In other toothbrushes, the bristles aresecured to the head without staples, in methods commonly known as“anchor free tufting”. In some toothbrushes, the bristles are organizedinto bristle tufts contained within retention or carrier elements orotherwise secured to the brush head neck. The retention elements serveto secure the bristle tufts within the brush head. During manufacture,the bristle tufts are inserted into openings in the brush head neck andsecured, or inserted into the hollow interior of the retention element,and the proximal portion of the bristles are melted together using a hotknife or heating plate or hot air to form a proximal end head portion tosecure the bristles in the retention elements, which, along with thebrush neck, are secured together by being surrounded with an injectionmolded flexible material, which is then allowed to cool in order to formthe final brush head.

The soft flexible material is vulnerable to dimensional changes causingdelamination or complete dissolution when exposed to oils, such asessential oils found in some organic toothpastes. As a result, the softflexible material can peel and become adhered to surrounding elements.In addition, the bristle tufts can become stuck together, become loose,and/or fall out completely from the brush head.

Accordingly, there is a need in the art for protecting the brush headfrom exposure to oils.

SUMMARY OF THE INVENTION

The present disclosure is directed to inventive methods formanufacturing a brush head with secured bristle tufts and improvedperformance characteristics. Various embodiments and implementationsherein are directed to manufacturing methods in which bristle tufts areaffixed with or to retention elements and are then encapsulated withinan injected flexible matrix material, resulting in a completed brushhead. In other arrangements, the bristle tufts are secured directly tothe brush head, and then encapsulated with an injected flexible matrixmaterial. Using the various embodiments and implementations herein,cost-effective and efficient production of brush heads with securedbristle tufts is substantially improved.

The invention includes a flexible matrix material injected around aportion of the brush neck, retention elements (if present) and bristletufts to retain the components in a brush head that can provide forvaried purposeful mobility of bristle tufts/flexibility of the flexiblematrix for improved and more complete teeth cleaning. Differentmaterials or combinations of material can be selected for the flexiblematrix material to achieve different performance characteristics. Anadditional protective coating is applied around the exterior of theflexible matrix material to provide improved performancecharacteristics, such as improved chemical impermeability. The brushheads disclosed and described herein can be used with any manual orpower toothbrush device.

Generally, in one aspect, a method for manufacturing a brush headassembly is provided. The method includes providing a plurality ofbristle tuft retention elements and a plurality of bristle tufts andinserting a respective bristle tuft into each of the bristle tuftretention elements. The method further includes securing a proximal endof each respective bristle tuft into each of the bristle tuft retentionelements and positioning a platen portion of a neck of the brush head inrelation to the proximal ends in a mold. The positioning of the platenportion of the neck defines a space in relation to the proximal ends forinjection of a flexible material. The method further includes injectingthe flexible material into the space in the mold to create a flexiblematerial matrix that at least partially encompasses the platen,retention elements, and the proximal ends and coating at least a portionof an exterior of the flexible material matrix with a protectivecoating. The protective coating can provide increased resistance to oneor more chemical compositions, oils or water. The protective coating canhave a thickness within the range of 50-200 μm.

In various embodiments, the step of securing the proximal ends of thebristle tufts includes the step of applying heat to the proximal ends ofthe bristle tufts at a temperature sufficient to at least partially meltthe proximal ends, or partially melt the proximal ends and a portion ofthe bristle tuft retention elements to create a proximal head portion.

In various embodiments, the flexible material matrix is made from avulcanized thermoplastic elastomer (TPE-V or TPV), or a Polyether BlockAmide (PEBA) material, a thermoplastic elastomer (TPE), a silicone orother flexible material.

In various embodiments, each of the neck, platen, and retention elementsare made from a material with a higher elastic modulus value than theflexible material, such as a thermoplastic polymer such as polypropylene(PP), or a polyamide-acrylonitrile-butadiene-styrene blend (PA/ABS).

In various embodiments, the protective coating is a thermoplasticvulcanisate (TPV) material, an ultraviolet (UV) curable acrylate, aurethane-based heat curable coating, or a silicone.

In various embodiments, the neck further includes a gate for injectionof the flexible material into the space.

Generally, in a further aspect, a method for manufacturing a brush headassembly is provided. The method includes providing a plurality ofbristle tuft retention elements and a plurality of bristle tufts andinserting a respective bristle tuft into each of the bristle tuftretention elements. The method further includes securing a proximal endof each respective bristle tuft into each of the bristle tuft retentionelements and positioning a platen portion of a neck of the brush head inrelation to the proximal ends in a mold. The positioning of the platenportion of the neck defines a space in relation to the proximal ends forinjection of a flexible material. The method further includes coating atleast a portion of the mold with a protective coating and injecting theflexible material into the space in the mold to create a flexiblematerial matrix that at least partially encompasses the platen,retention elements, and the proximal ends and forming a layer on top ofthe flexible material matrix with the protective coating from the mold.In various embodiments, the coating is applied to an interior surface ofthe mold prior to injection of the flexible material.

In various embodiments, the flexible material matrix is made from avulcanized thermoplastic elastomer (TPE-V or TPV), or a Polyether BlockAmide (PEBA) material, a thermoplastic elastomer (TPE), a silicone orother flexible material.

In various embodiments, each of the neck, platen, and retention elementsare made from a material with a higher elastic modulus value than theflexible material, such as a thermoplastic polymer such as polypropylene(PP), or a polyamide-acrylonitrile-butadiene-styrene blend (PA/ABS).

In various embodiments, the protective coating is a thermoplasticvulcanisate (TPV) material, an ultraviolet (UV) curable acrylate, aurethane-based heat curable coating, or a silicone.

In various embodiments, the neck further includes a gate for injectionof the flexible material into the space.

Generally, in another aspect, a brush head for a toothbrush is provided.The brush head includes a neck having a platen portion, a plurality ofbristle tufts, each of which comprises a plurality of bristle strands,and a plurality of retention elements, each configured to receive atleast one of the plurality of bristle tufts. After the bristle tufts areinserted into the retention elements, the proximal ends of the bristletufts are secured into the retention elements. The brush head furtherincludes a flexible material matrix formed by injection molding aflexible material around least a portion of the brush neck platen, theplurality of retention elements, and the proximal ends to secure thecomponents together and a protective coating around at least a portionof an exterior of the flexible material matrix.

It should be appreciated that all combinations of the foregoing conceptsand additional concepts discussed in greater detail below (provided suchconcepts are not mutually inconsistent) are contemplated as being partof the inventive subject matter disclosed herein. In particular, allcombinations of claimed subject matter appearing at the end of thisdisclosure are contemplated as being part of the inventive subjectmatter disclosed herein.

These and other aspects of the invention will be apparent from andelucidated with reference to the embodiment(s) described hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, like reference characters generally refer to the sameparts throughout the different views. Also, the drawings are notnecessarily to scale, emphasis instead generally being placed uponillustrating the principles of the invention.

FIG. 1 is a schematic representation of a side view of a brush headassembly in accordance with an embodiment.

FIG. 2 is a schematic representation of a reverse view of a brush headassembly in accordance with an embodiment.

FIG. 3A is a flowchart of a method for manufacturing a brush headassembly with a protective coating or barrier in accordance with anembodiment.

FIG. 3B is a flowchart of a method for manufacturing a brush headassembly with a protective coating or barrier in accordance with anembodiment.

FIGS. 4A-4C are schematic representations of a method for manufacturinga brush head assembly with bristle tufts retained within a flexiblematerial matrix in accordance with an embodiment.

DETAILED DESCRIPTION OF EMBODIMENTS

The present disclosure describes various embodiments of a method formanufacturing a brush head assembly with bristle tufts retained within aflexible material matrix such that the brush head assembly is resistantor immune against oils. More generally, Applicants have recognized andappreciated that it would be beneficial to provide a brush head formedfrom a flexible matrix, which can be beneficial to a brush head'sfunction, especially in powered toothbrush devices. A particular goal ofutilization of certain embodiments of the present disclosure is theability to efficiently manufacture brush heads with improved retentionof the bristle tufts and other components while providing good brushingperformance.

In view of the foregoing, various embodiments and implementations aredirected to a method in which a bristle tuft is affixed to or within aretention element or directly to a brush head neck, and is then embeddedwithin a flexible material matrix. The bristle tuft is inserted into theretention element and is secured to or within the retention element.Alternatively, the bristle tufts are attached directly in or to thebrush head neck by means of holes, and/or other securing methods, suchas melting, gluing, laser welding or other securing methods. As yetanother alternative, a retaining head portion is created on the bristletuft which is then unable to pass through the retention element. Thebristle tuft and retention element (if present) are then embedded withina flexible material matrix to form the brush head. The flexible materialmatrix is then coated with a protective coating or barrier to preventthe matrix from experiencing dimensional changes when exposed to oils orthe slow down the diffusion of oils into the matrix.

Brush Head Assembly

Referring to FIG. 1, in one embodiment, a schematic representation of abrush head assembly 100 is provided. The brush head includes a neck 40,which can be coupled to any manual brush shaft, or, more preferably, toany actuator and drive shaft (not shown) made or suitable for oral caredevices now known or to be developed. The brush head also includes aplurality of bristle tufts 21, each of which comprises a plurality ofbristle strands. Each bristle tuft includes a proximal end and a freeend, where the proximal end of each bristle tuft is retained within thebrush head assembly 100.

According to an embodiment as shown in FIG. 1, each bristle tuft 21 isretained within a hollow portion of a retention element 50. The proximalend of the bristle tuft and at least a portion of the retention elementsand the portion of the neck that is the platen 42 are encapsulatedwithin an injection molded flexible material matrix 30. In anotherembodiment (not shown), the proximal end of the bristle tufts 21 aresecured directly in or to the platen 42 by means of securing the endsinto holes in the neck, or melting, gluing, laser welding or othersecuring method. According to an embodiment, the flexible materialmatrix 30 is preferably made from a vulcanized thermoplastic elastomer(TPE-V or TPV), a Polyether Block Amide (PEBA) material, a thermoplasticelastomer (TPE), silicone, or any other material suitable for injectionmolding that remains flexible after curing. The neck 40, platen 42, andthe retention elements 50 are preferably made from a material with ahigher elastic modulus value than the flexible material matrix 30,typically a thermoplastic polymer such as polypropylene (PP), or apolyamide-acrylonitrile-butadiene-styrene blend (PA/ABS). The flexiblematerial matrix 30 includes an additional protective coating applied tothe exterior of the flexible material matrix 30 to provide improvedmaterial performance, such as increased resistance to one or morechemical compositions, oils, or water, for example, as further describedbelow.

Referring to FIG. 2, a reverse schematic representation of a brush headassembly 100 is provided. One or more gates 41 is shown on the back sideof the neck 40. This gate 41 is used for the injection molding of theflexible material matrix 30, as described below.

Many other embodiments of brush head assembly 100 are possible,including other configurations of neck 40, platen 42, bristle tufts 21,retention elements 50 (if used), and/or flexible material matrix 30.

Methods of Brush Head Manufacture

Referring to FIG. 3A, in one embodiment, is a method 200 formanufacturing one or more of the various brush head embodiments andimplementations described or otherwise envisioned herein. In step 210 ofthe method of manufacture depicted in FIG. 3A, a plurality of retentionelements 50 are provided. Retention elements 50 can be of variousshapes, sizes, and/or configurations described or otherwise envisionedherein. For example, the plurality of retention elements 50 can be thesame size and shape, or multiple different sizes and shapes.

At step 220 of the method, a bristle tuft 21 (which comprises aplurality of bristle strands) is inserted into each of the plurality ofretention elements 50. Each of the bristle tufts 21 includes a proximalend and a free end, with the proximal end being inserted into theretention element.

At step 230 of the method, the bristle tufts are secured in theretention elements. In one arrangement, heat is applied to the proximalend of the plurality of bristle tufts 21 to create a melted proximal endhead portion 26 that secures the bristle tufts in the retentionelements. Proximal end head portion 26 is the melted ends of the bristletuft 21, or the melted ends of the bristle tufts and at least a portionof the retention elements, depending on the composition, and thereforethe melting point, of the materials used for each component. Thisproximal end head portion is of a sufficient size that it cannot moveback through the retention element, thereby securing the bristle tuft inthe hollow ring of the retention element.

In step 240 of method 200 depicted in FIG. 3A, the brush head neck 40 ispositioned to put the platen 42 portion of the neck in the properlocation in relation to the retention elements 50 with the bristle tufts21 inserted, as shown in FIG. 4A. Typically, the platen 42 is positionedjust above the proximal end head portion 26 of the bristle tufts 21 inthe retaining elements 50. Platen 42 can be properly positioned using amold, for example, or other positioning mechanism. This creates a space92 into which the flexible material can be injected.

In step 250 of the method, a flexible material is molded, typically bymeans of injection molding, into the space 92 between and around theplaten 42, the head portion 26 of the bristle tufts, and the retentionelements 50. According to an embodiment, as shown in FIG. 4B, neck 40,platen 42 of the brush head, and the retention elements and bristletufts are held in a mold while the flexible material is injected intothe space 92. As shown in FIG. 2, neck 40 comprises one or more gates 41that allows the molten flexible material to be injected into the cavityof the mold. The molded flexible material forms a flexible materialmatrix 30, as shown in FIGS. 4B and 4C. The neck 40, platen 42, and theretention elements 50 are preferably made from a material with a higherelastic modulus value than the flexible material matrix 30, typically athermoplastic polymer such as polypropylene (PP), or apolyamide-acrylonitrile-butadiene-styrene blend (PA/ABS).

As shown in step 260 of FIG. 3A and in FIG. 4C, an additional protectivecoating 60 is applied to all or a portion of the exterior of theflexible material matrix 30 to provide improved material performance,such as increased resistance to one or more chemical compositions, oils,or water, for example. The protective coating, which can be transparentpreferably, can be sprayed or over molded on the flexible materialmatrix 30 such that the protective coating forms a thin, uniform coatingon all or a portion of the exterior of the flexible material matrix 30.The protective coating can have a thickness that is greater than 50 μmand less than 200 μm.

Various materials can be used to provide the protective coating,depending on the desired performance enhancement. For example, thecoating could be a thermoplastic vulcanisate (TPV) material, a UVcurable acrylate, a silicone, a heat curable (e.g., urethane-based)coating, or other coatings applied over the exterior of the flexiblematerial matrix to improve chemical resistance to oils, water, and otherchemicals. The composition of the protective coating must be compatiblewith the composition of the flexible material matrix to which it isbeing applied to ensure good bonding.

Referring to FIG. 3B, in one embodiment, is a method 300 formanufacturing one or more of the various brush head embodiments andimplementations described or otherwise envisioned herein. Steps 310,320, 330, and 340 are the same as steps 210, 220, 230, and 240,respectively, in the method 200 in FIG. 3A. However, as shown in step350 of FIG. 3B, an additional protective coating 60 can be applied toall or a portion of the interior surface of the mold prior to injectingthe flexible material. The protective coating can be sprayed orotherwise applied to the interior of the mold in step 350. Theprotective coating can be various materials as described above,depending on the desired performance enhancement. For example, thecoating could be a thermoplastic vulcanisate (TPV) material, a UVcurable acrylate (e.g., a polyurethane acrylate UV coating), a heatcurable (e.g., urethane-based) coating, a silicone, or other coatingsapplied over the exterior of the flexible material matrix to improvechemical resistance to oils, water, and other chemicals. The compositionof the protective coating must be compatible with the composition of theflexible material matrix to which it is being applied to ensure goodbonding.

In step 360 of the method of FIG. 3B, a flexible material is injectedinto the mold so that the protective coating on the inside of the moldadheres to the flexible material as the flexible material is molded. Theprotective coating 60 adheres to the exterior surface of the flexiblematerial matrix 30. The flexible material is molded, typically by meansof injection molding, into the space 92 between and around the platen42, the head portion 26 of the bristle tufts, and the retention elements50. According to an embodiment, as shown in FIG. 4B, neck 40, platen 42of the brush head, and the retention elements and bristle tufts are heldin a mold while the flexible material 30 is injected into the space 92.As shown in FIG. 2, neck 40 comprises one or more gates 41 that allowthe molten flexible material to be injected into the cavity of the mold.The molded flexible material forms a flexible material matrix 30 with aprotective coating adhered thereto, as shown in FIG. 4C. The neck 40,platen 42, and the retention elements 50 are preferably made from amaterial with a higher elastic modulus value than the flexible materialmatrix 30, typically a thermoplastic polymer such as polypropylene (PP),or a polyamide-acrylonitrile-butadiene-styrene blend (PA/ABS).

The protective coating 60 described or otherwise envisioned herein canalso be applied to the flexible material using masks or caps to protectthe retention rings and bristles from being coated. The

All definitions, as defined and used herein, should be understood tocontrol over dictionary definitions, definitions in documentsincorporated by reference, and/or ordinary meanings of the definedterms.

The indefinite articles “a” and “an,” as used herein in thespecification and in the claims, unless clearly indicated to thecontrary, should be understood to mean “at least one.”

The phrase “and/or,” as used herein in the specification and in theclaims, should be understood to mean “either or both” of the elements soconjoined, i.e., elements that are conjunctively present in some casesand disjunctively present in other cases. Multiple elements listed with“and/or” should be construed in the same fashion, i.e., “one or more” ofthe elements so conjoined. Other elements may optionally be presentother than the elements specifically identified by the “and/or” clause,whether related or unrelated to those elements specifically identified.

As used herein in the specification and in the claims, “or” should beunderstood to have the same meaning as “and/or” as defined above. Forexample, when separating items in a list, “or” or “and/or” shall beinterpreted as being inclusive, i.e., the inclusion of at least one, butalso including more than one, of a number or list of elements, and,optionally, additional unlisted items. Only terms clearly indicated tothe contrary, such as “only one of” or “exactly one of,” or, when usedin the claims, “consisting of,” will refer to the inclusion of exactlyone element of a number or list of elements. In general, the term “or”as used herein shall only be interpreted as indicating exclusivealternatives (i.e. “one or the other but not both”) when preceded byterms of exclusivity, such as “either,” “one of,” “only one of,” or“exactly one of.”

As used herein in the specification and in the claims, the phrase “atleast one,” in reference to a list of one or more elements, should beunderstood to mean at least one element selected from any one or more ofthe elements in the list of elements, but not necessarily including atleast one of each and every element specifically listed within the listof elements and not excluding any combinations of elements in the listof elements. This definition also allows that elements may optionally bepresent other than the elements specifically identified within the listof elements to which the phrase “at least one” refers, whether relatedor unrelated to those elements specifically identified.

It should also be understood that, unless clearly indicated to thecontrary, in any methods claimed herein that include more than one stepor act, the order of the steps or acts of the method is not necessarilylimited to the order in which the steps or acts of the method arerecited.

In the claims, as well as in the specification above, all transitionalphrases such as “comprising,” “including,” “carrying,” “having,”“containing,” “involving,” “holding,” “composed of,” and the like are tobe understood to be open-ended, i.e., to mean including but not limitedto. Only the transitional phrases “consisting of” and “consistingessentially of” shall be closed or semi-closed transitional phrases,respectively.

While several inventive embodiments have been described and illustratedherein, those of ordinary skill in the art will readily envision avariety of other means and/or structures for performing the functionand/or obtaining the results and/or one or more of the advantagesdescribed herein, and each of such variations and/or modifications isdeemed to be within the scope of the inventive embodiments describedherein. More generally, those skilled in the art will readily appreciatethat all parameters, dimensions, materials, and configurations describedherein are meant to be exemplary and that the actual parameters,dimensions, materials, and/or configurations will depend upon thespecific application or applications for which the inventive teachingsis/are used. Those skilled in the art will recognize, or be able toascertain using no more than routine experimentation, many equivalentsto the specific inventive embodiments described herein. It is,therefore, to be understood that the foregoing embodiments are presentedby way of example only and that, within the scope of the appended claimsand equivalents thereto, inventive embodiments may be practicedotherwise than as specifically described and claimed. Inventiveembodiments of the present disclosure are directed to each individualfeature, system, article, material, kit, and/or method described herein.In addition, any combination of two or more such features, systems,articles, materials, kits, and/or methods, if such features, systems,articles, materials, kits, and/or methods are not mutually inconsistent,is included within the inventive scope of the present disclosure.

1. A method for manufacturing a brush head, the method comprising thesteps of: providing a plurality of bristle tuft retention elements and aplurality of bristle tufts; inserting a respective bristle tuft intoeach of the bristle tuft retention elements; securing a proximal end ofeach respective bristle tuft into each of the bristle tuft retentionelements; positioning a platen portion of a neck of the brush head inrelation to the proximal ends in a mold, wherein the positioning of theplaten portion of the neck defines a space in relation to the proximalends for injection of a flexible material; injecting the flexiblematerial into the space in the mold to create a flexible material matrixthat at least partially encompasses the platen, retention elements, andthe proximal ends; and coating at least a portion of an exterior of theflexible material matrix with a protective coating.
 2. The method ofclaim 1, wherein the step of securing the proximal ends of the bristletufts comprises the step of: applying heat to the proximal ends of thebristle tufts at a temperature sufficient to at least partially melt theproximal ends, or partially melt the proximal ends and a portion of thebristle tuft retention elements to create a proximal head portion. 3.The method of claim 1, wherein the flexible material matrix is made froma vulcanized thermoplastic elastomer (TPE-V or TPV), or a PolyetherBlock Amide (PEBA) material, a thermoplastic elastomer (TPE), a siliconeor other flexible material.
 4. The method of claim 1, wherein each ofthe neck, platen, and retention elements are made from a material with ahigher elastic modulus value than the flexible material, such as athermoplastic polymer such as polypropylene (PP), or apolyamide-acrylonitrile-butadiene-styrene blend (PA/ABS).
 5. The methodof claim 1, wherein the protective coating provides increased resistanceto one or more chemical compositions, oils or water.
 6. The method ofclaim 1, wherein the protective coating is a thermoplastic vulcanisate(TPV) material, an ultraviolet (UV) curable acrylate, a urethane-basedheat curable coating, or a silicone.
 7. The method of claim 1, whereinthe neck further comprises a gate for injection of the flexible materialinto said space.
 8. The method of claim 1, wherein the coating has athickness within the range of 50-200 μm.
 9. A method for manufacturing abrush head, the method comprising the steps of: providing a plurality ofbristle tuft retention elements and a plurality of bristle tufts;inserting a respective bristle tuft into each of the bristle tuftretention elements; securing a proximal end of each respective bristletuft into each of the bristle tuft retention elements; positioning aplaten portion of a neck of the brush head in relation to the proximalends in a mold, wherein the positioning of the platen portion of theneck defines a space in relation to the proximal ends for injection of aflexible material; coating at least a portion of the mold with aprotective coating; and injecting the flexible material into the spacein the mold to create a flexible material matrix that at least partiallyencompasses the platen, retention elements, and the proximal ends andforming a layer on top of the flexible material matrix with theprotective coating from the mold.
 10. The method of claim 9, wherein thecoating is applied to an interior surface of the mold prior to injectionof the flexible material.
 11. The method of claim 9, wherein theflexible material matrix is made from a vulcanized thermoplasticelastomer (TPE-V or TPV), or a Polyether Block Amide (PEBA) material, athermoplastic elastomer (TPE), a silicone or other flexible material.12. The method of claim 9, wherein each of the neck, platen, andretention elements are made from a material with a higher elasticmodulus value than the flexible material, such as a thermoplasticpolymer such as polypropylene (PP), or apolyamide-acrylonitrile-butadiene-styrene blend (PA/ABS).
 13. The methodof claim 9, wherein the protective coating is a thermoplasticvulcanisate (TPV) material, an ultraviolet (UV) curable acrylate, aurethane-based heat curable coating, or a silicone.
 14. The method ofclaim 9, wherein the neck further comprises a gate for injection of theflexible material into said space.
 15. A brush head, comprising: a neckhaving a platen portion; a plurality of bristle tufts, each of whichcomprises a plurality of bristle strands; a plurality of retentionelements, each configured to receive at least one of the plurality ofbristle tufts, wherein after the bristle tufts are inserted into theretention elements, the proximal ends of the bristle tufts are securedinto the retention elements; a flexible material matrix formed byinjection molding a flexible material around least a portion of thebrush neck platen, the plurality of retention elements, and the proximalends to secure the components together; and a protective coating (60)around at least a portion of an exterior of the flexible material matrix(30).